Biomass Energy: Understanding what it is and how it works

Biomass energy is an eco-friendly alternative to commonly used, climate change-inducing fossil fuels. As a renewable energy source, bioenergy can reduce an individual’s carbon footprint by over 80 per cent.

As our society is becoming more aware of its impact on the planet, more and more people are learning that investing in green energy options (such as renewable resources) is an affordable, and easy way to reduce the environmental impact of electricity generation.

What is biomass energy?

Biomass energy is a cleaner energy source created from natural, biological materials. These renewable resources include living or recently dead organisms including plants and animals, and their byproducts. Using the sun’s energy via photosynthesis, a highly-efficient energy system known as cogeneration (sometimes known as Combined Heat and Power) results in both electricity and heat. So long as there’s sunlight to nourish the soil in which biomass sources grow, this is one of the most renewable resources for energy creation.

Where does the fuel come from?

Bioenergy uses biomass to create fuel. Biomass is made of organic materials1 which are plant or animal derived – and that are grown, collected, or harvested to create energy. Examples of biomass include wood waste, bagasse (sugar cane residues), and animal fats. This waste is processed in different ways to create energy1. One method includes directly burning the biomass to release energy in the form of heat which can be used to generate electricity. There’s also chemical conversion. This is where chemicals are used to break the biomass down, where it takes the form of biogas or liquid biofuels. These can then be used to create electricity, as well as fuel for transport.

Cogeneration and the benefits

Cogeneration is the simultaneous creation of two forms of biomass energy – heat and electricity. By using the waste heat (steam) to create the electricity it can significantly reduce energy costs and greenhouse gas emissions by up to two-thirds . In addition to reducing operating costs, cogeneration is 80% more efficient than conventional energy sources2.

For example, a hospital cogeneration plant could produce some of the electricity and all the hot water needed for its laundry and hot water system from the waste heat it generates. Similarly, office buildings could produce power for electricity and air conditioning from the waste heat generated by its air conditioning engines.

Where does cogeneration take place?

All-natural, biological sources are transported to specialist plants where dirt and contaminants are removed. The material is then processed and stored in fuel bins, ready to go through the cogeneration process.

The benefits of Biomass energy

The advantages of renewable energy are endless. Firstly, Biomass energy indirectly reduces the amount of coal production needed to create electricity and heat, thus reducing our carbon dioxide emissions. As we’ve discussed, it’s also much more efficient than fossil fuels. In fact, according to the Clean Energy Council of Australia it can be up to 80% more efficient than conventional energy sources2.

Combustion typically has an electrical efficiency of only 20-35%, but co-generation techniques can reach energy efficiencies of over 85%3. Modern thermal-only bioenergy systems typically operate at or above 85% efficiency and are much simpler and cheaper to install and run than co-generation systems. Even the wastewater generated by the co-generation process is recycled and passed through treatment systems before being used to irrigate local cane farms.

Another benefit becomes apparent when you compare it to traditional fossil fuels. Specifically in relation to how long it takes for bioenergy sources to be replenished. Biomass removes carbon from the atmosphere while it’s growing4, and returns it as it’s burned. If it’s managed in a sustainable way, biomass should be cultivated as part of a crop that’s continually replenished. This ensures that the biomass crop is taking up C02 from the atmosphere, at the same time as it’s put back in as a result of combustion from the previous harvest.

Just to paint this in perspective. In contrast to biomass and bioenergy, when a fossil fuel is burnt it takes hundreds of millions of years to be replenished4.

Biomass energy and sustainable management

The close association to farms, forests, and other ecosystems where biomass raw materials are obtained, means biomass energy has the potential for environmental and social consequences. Affected areas including soils, water resources, biodiversity, ecosystem function and local communities will vary depending on the way in which biomass energy is produced and harvested. More sustainable approaches include choosing management practices that reduce adverse impacts and complement local land-management objectives, such as farm preservation, forest protection, food production and wildlife management.

Biomass energy and its environmental impact

In nature, if biomass is left lying around on the ground it’ll break down over a long period of time, releasing carbon dioxide and its store of energy slowly. By burning biomass via cogeneration, its store of energy is released quickly.

Converting biomass for use in energy production simply imitates the naturally-occurring process at a faster rate – without the greenhouse emissions. Bioenergy does have high transport and handling costs. Transport trucks use fossil fuels, and where manure and other waste products are involved, controlling the odour and potential disease must be considered.

The future is green energy

Biomass energy is becoming more and more of a realistic option for Australians. With over 100 cogeneration plants active in Australia that combine heat and power production from biomass, we’re slowly building a future that reduces our reliance on climate change-inducing fossil fuels.

If you want to support renewable energy and reduce your carbon footprint, call us on 13 19 20.

iSelect does not compare all products in the market. Not all products are available at all times.